PrefaceThe past 35 years have seen the emergence of a growing desire worldwide that positiveactions be taken to restore and protect the environment from the degrading effects of all formsof pollution – air, water, soil, thermal, radioactive, and noise. Since pollution is a direct orindirect consequence of waste, the seemingly idealistic demand for “zero discharge” can beconstrued as an unrealistic demand for zero waste. However, as long as waste continues toexist, we can only attempt to abate the subsequent pollution by converting it to a less noxiousform. Three major questions usually arise when a particular type of pollution has beenidentiﬁed: (1) How serious is the pollution? (2) Is the technology to abate it available? and(3) Do the costs of abatement justify the degree of abatement achieved? This book is one ofthe volumes of the Handbook of Environmental Engineering series. The principal intention ofthis series is to Giúp readers formulate answers to the above three questions.The traditional approach of applying tried-and-true solutions to speciﬁc pollution pro-blems has been a major contributing factor to the success of environmental engineering, andhas accounted in large measure for the establishment of a “methodology of pollution control”.However, the realization of the ever-increasing complexity and interrelated nature of currentenvironmental problems renders it imperative that intelligent planning of pollution abatementsystems be undertaken. Prerequisite to such planning is an understanding of the performance,potential, and limitations of the various methods of pollution abatement available for environ-mental scientists and engineers. In this series of handbooks, we review at a tutorial levela broad spectrum of engineering systems (processes, operations, and methods) currentlybeing utilized, or of potential utility, for pollution abatement. We believe that the uniﬁedinterdisciplinary approach presented in these handbooks is a logical step in the evolution ofenvironmental engineering.Treatment of the various engineering systems presented shows how an engineeringformulation of the subject ﬂows naturally from the fundamental principles and theories ofchemistry, microbiology, physics, and mathematics. This emphasis on fundamental sciencerecognizes that engineering practice has in recent years become more ﬁrmly based onscientiﬁc principles rather than on its earlier dependency on empirical accumulation offacts. It is not intended, though, to neglect empiricism where such data lead quickly to themost economic design; certain engineering systems are not readily amenable to fundamen-tal scientiﬁc analysis, and in these instances we have resorted to less science in favor ofmore art and empiricism.Since an environmental engineer must understand science within the context of applica-tion, we ﬁrst present the development of the scientiﬁc basis of a particular subject, followedby the exposition of the pertinent design concepts and operations, and detailed explanationsof their applications to environmental quality control or remediation. Throughout the series,methods of practical design and calculation are illustrated by numerical examples. Theseexamples clearly demonstrate how organized, analytical reasoning leads to the most directand clear solutions. Wherever possible, pertinent cost data have been provided.Our treatment of pollution abatement engineering is offered in the belief that a trainedengineer should more ﬁrmly understand fundamental principles, be more aware of thesimilarities and/or differences among many of the engineering systems, and exhibit greaterﬂexibility and originality in the deﬁnition and innovative solution of environmental pollutionproblems. In short, an environmental engineer should by conviction and practice be morereadily adaptable to change and progress.Coverage of the unusually broad ﬁeld of environmental engineering has demanded anexpertise that could only be provided through multiple authorships. Each author (or group ofauthors) was permitted to employ, within reasonable limits, the customary personal style inorganizing and presenting a particular subject area; consequently, it has been difﬁcult to treatall subject materials in a homogeneous manner. Moreover, owing to limitations of space,some of the authors’ favored topics could not be treated in great detail, and many lessimportant topics had to be merely mentioned or commented on brieﬂy. All authors haveprovided an excellent list of references at the end of each chapter for the beneﬁt of theinterested readers. As each chapter is meant to be self-contained, some mild repetition amongthe various texts was unavoidable. In each case, all omissions or repetitions are the responsi-bility of the editors and not the individual authors.With the current trend toward metrication,the question of using a consistent system of units has been a problem.Wherever possible, theauthors have used the British system (fps) along with the metric equivalent (mks, cgs, or SIU)or vice versa. The editors sincerely hope that this redundancy of units’ usage proves to beuseful rather than being disruptive to the readers.The goals of the Handbook of Environmental Engineering series are: (1) to cover entireenvironmental ﬁelds, including air and noise pollution control, solid waste processing andresource recovery, physicochemical treatment processes, biological treatment processes,biosolids management, ﬂotation technology, membrane technology, desalination technol-ogy, water resources, natural control processes, radioactive waste disposal, and thermalpollution control, and (2) to employ a multimedia approach to environmental pollutioncontrol since air, water, soil, and energy are all interrelated.This book is Vol. 13 of the Handbook of Environmental Engineering series, which hasbeen designed to serve as an advanced chemical and environmental engineering textbook aswell as a comprehensive reference book. We hope and expect that it proves of equal highvalue to advanced undergraduate and graduate students, to designers of water and wastewatertreatment systems, and to scientists and researchers. The editors welcome comments fromreaders in all of these categories. It is our hope that the book not only provides information onmembrane and desalination technologies, but also serves as a basis for advanced study orspecialized investigation of the theory and practice of various membrane processes andsystems.This book, Membrane and Desalination Technologies, covers topics on principles ofmembrane technology, desalination requirements, historical developments, membranefouling characterization, drinking water disinfection, regulations and determination of logremovals, membrane systems planning and design, industrial waste treatment, municipalwaste treatment, wastewater reclamation, food industry material separation, resourcerecovery, adsorption desalination, bioﬁltration, membrane bioreactor, thermal distillation,vi Prefaceelectrodialysis desalination, reverse osmosis desalination, point of use membrane applications,oil–water separation applications, and future membrane and desalination developments.The editors are pleased to acknowledge the encouragement and support received from theircolleagues and the publisher during the conceptual stages of this endeavor.We wish to thankthe contributing authors for their time and effort, and for having patiently borne our reviewsand numerous queries and comments.We are very grateful to our respective families for theirpatience and understanding during some rather trying times.Lawrence K. Wang, Lenox, MA, USAJiaping Paul Chen, Kent Ridge, SingaporeYung-Tse Hung, Cleveland, OH, USANazih K. Shammas, Lenox, MA, USA